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951.
介绍了"低碳概念"提出的大背景及低碳经济的发展过程,阐述了中国经济发展走低碳之路的必要性,提出了中国经济应对低碳挑战的总体战略及主要措施,以及若干亟待研究解决的问题. 相似文献
952.
Roel Massink Mark Zuidgeest Jaap Rijnsburger Olga L. Sarmiento Martin van Maarseveen 《Natural resources forum》2011,35(2):100-111
The reduction of CO2 emissions constitutes one of the largest challenges of the current era. Sustainable transportation, and especially cycling, can contribute to the mitigation of CO2 emissions since cycling possesses an intrinsic zero‐emission value. Few studies have been conducted that appraise the CO2 reduction potential of cycling. Opportunity costs enable the estimation of avoided CO2 emissions resulting from bicycle trips. The methodology developed in this research allows the attribution of a climate value to cycling by substituting bicycle trips with their most likely alternative transportation modes and calculating the resulting additional CO2 emissions. The methodology uses data on the current modal shares of cycling mobility, the competition of cycling with other transportation modes, and CO2 emission factors to calculate the climate value of cycling. When it is assumed that the avoided CO2 emissions of cycling mobility could be traded on financial carbon markets, the climate value of cycling represents a monetary value. Application of the methodology to the case of Bogotá, Colombia — a city with a current bicycle modal share of 3.3% on a total of 10 million daily trips — results in a climate value of cycling of 55,115 tons of CO2 per year, corresponding to an economic value of between 1 and 7 million US dollars when traded on the carbon market. 相似文献
953.
Pasquarè FA Tormey D Vezzoli L Okrostsvaridze A Tutberidze B 《Journal of environmental management》2011,92(7):1774-1782
In this work we identify and quantify new seismic and volcanic risks threatening the strategic Caspian oil and gas pipelines through the Republic of Georgia, in the vicinity of the recent Abuli Samsari Volcanic Ridge, and evaluate risk reduction measures, mitigation measures, and monitoring. As regards seismic risk, we identified a major, NW-SE trending strike-slip fault; based on the analysis of fault planes along this major transcurrent structure, an about N-S trend of the maximum, horizontal compressive stress (σ1) was determined, which is in good agreement with data instrumentally derived after the 1986, M 5.6 Paravani earthquake and its aftershock. Particularly notable is the strong alignment of volcanic vents along an about N-S trend that suggests a magma rising controlled by the about N-S-directed σ1. The original pipeline design included mitigation measures for seismic risk and other geohazards, including burial of the pipeline for its entire length, increased wall thickness, block valve spacing near recognized hazards, and monitoring of known landslide hazards. However, the design did not consider volcanic risk or the specific seismic hazards revealed by this study. The result of our analysis is that the Baku-Tbilisi-Ceyhan (BTC) oil pipeline, as well as the Baku-Tbilisi-Erzerum South Caucasian natural gas pipeline (SCP) were designed in such a way that they significantly reduce the risk posed by the newly-identified geohazards in the vicinity of the Abuli-Samsari Ridge. No new measures are recommended for the pipeline itself as a result of this study. However, since the consequences of long-term shut-down would be very damaging to the economies of Western Europe, we conclude that the regionally significant BTC and SCP warrant greater protections, described in the final section of or work. The overall objective of our effort is to present the results in a matrix framework that allows the technical information to be used further in the decision-making process, with the goal of reducing the uncertainty in the final decision. This approach is applicable to the study of risks in other pipeline systems. 相似文献
954.
为研究长时间单调驾驶对驾驶员疲劳、嗜睡、反应时间和驾驶速度的确切影响,以合作企业3系重卡为操作对象进行了一组真实驾驶条件试验。在自愿的基础上随机地从合作企业物流公司选择12名经验丰富的驾驶员作为试验的驾驶员样本。试验采用主观评分方法记录试验者的嗜睡和疲劳状况,所有数据分析基于统计学软件PASW Statistic 18.0。试验结果表明长时间单调驾驶会导致驾驶员疲劳和嗜睡,而疲劳和嗜睡在一定的程度上会导致驾驶速度的加快,却没有导致驾驶员反应时间的显著变化。在持续驾驶3 h之后驾驶员的疲劳和驾驶绩效发生了明显劣化,故从安全的角度考虑应以2~3 h为界合理安排司机的作业负荷和绩效考评。 相似文献
955.
宋昕旖聂瑾璐杨梦涵喻懋椿陶梁明冯虎元潘建斌 《应用与环境生物学报》2022,(6):1527-1533
Polygonum viviparum, which reproduces sexually and asexually, is widely distributed in the Qinghai-Tibet Plateau, and its reproduction strategies are very sensitive to changes in the environment. This study aimed to elucidate the effect of altitude on the photosynthetic characteristics and reproductive strategies of P. viviparum. This study was conducted to investigate the responses of photosynthetic, vegetative, and reproductive traits of P. viviparum populations along six altitudinal gradients in the eastern part of the Qilian Mountains in China. Our results indicated that, with increasing altitude, the net photosynthetic rate of P. viviparum showed an increasing trend, reaching its maximum value (14.39 μmol m–2 s–1) at 3 700 m above sea level. The transpiration rate showed an increasing trend, followed by a decreasing trend, and the intercellular CO2 concentration did not differ significantly between altitudes. With increasing altitude, the plant height and leaf area of P. viviparum showed a downward trend, the aboveground and underground biomass decreased, and the specific leaf area initially decreased and then increased. However, the leaf greenness index showed an upward trend, and the number of stomata in the upper and lower epidermis of leaves initially increased and then decreased. With increasing altitude, the proportion of inflorescence length per plant (the ratio of inflorescence length to plant height), the proportion of bulbil length per inflorescence (the ratio of bulbil length to inflorescence height), and the proportion of the number of bulbils per inflorescence (the ratio of the number of bulbils to the total number of flowers and bulbils) showed an increasing trend. Air temperature and light intensity are the major environmental factors affecting the photosynthetic characteristics and functional traits of P. viviparum. Thus, P. viviparum is exposed to more environmental stresses and obtains less energy when altitude increases, but it adapts to the harsh alpine environment by increasing the photosynthetic capability per unit area. With increasing altitude, P. viviparum populations may be sustained by investing less energy in vegetation and more in reproduction, especially asexual reproduction. © 2022 Science Press. All rights reserved. 相似文献
956.
The power sector in Thailand is the largest contributor to CO2 emissions. There is high potential to mitigate CO2 emission via alternative power generating plants. Alternative plants considered in this study include nuclear plants, integrated gasification combined cycle plants, biomass-based plants and supercritical thermal power plants. The biomass-based plants considered here are fueled with four types of biomass; paddy husk, municipal solid waste (MSW), fuel wood and corncob. The methodology for the optimal expansion plan of the power generating system over the planning horizon is based on the least-cost approach. The results from the least-cost planning analyses show that the nuclear alternative has the highest potential to mitigate not only CO2 but also other airborne emissions. Moreover, the nuclear option is the most effective abatement strategy for CO2 reduction due to its negative incremental cost of CO2 reduction. 相似文献
957.
TREVOR J. C. BEEBEE 《Conservation biology》2013,27(4):657-668
Road mortality is a widely recognized but rarely quantified threat to the viability of amphibian populations. The global extent of the problem is substantial and factors affecting the number of animals killed on highways include life‐history traits and landscape features. Secondary effects include genetic isolation due to roads acting as barriers to migration. Long‐term effects of roads on population dynamics are often severe and mitigation methods include volunteer rescues and under‐road tunnels. Despite the development of methods that reduce road kill in specific locations, especially under‐road tunnels and culverts, there is scant evidence that such measures will protect populations over the long term. There also seems little likelihood that funding will be forthcoming to ameliorate the problem at the scale necessary to prevent further population declines. Efectos de la Mortalidad en Carreteras y Medidas de Mitigación en Poblaciones de Anfibios Beebee 相似文献
958.
TOBY A. GARDNER AMREI VON HASE SUSIE BROWNLIE JONATHAN M. M. EKSTROM JOHN D. PILGRIM CONRAD E. SAVY R. T. THEO STEPHENS JO TREWEEK GRAHAM T. USSHER GERRI WARD KERRY TEN KATE 《Conservation biology》2013,27(6):1254-1264
Businesses, governments, and financial institutions are increasingly adopting a policy of no net loss of biodiversity for development activities. The goal of no net loss is intended to help relieve tension between conservation and development by enabling economic gains to be achieved without concomitant biodiversity losses. biodiversity offsets represent a necessary component of a much broader mitigation strategy for achieving no net loss following prior application of avoidance, minimization, and remediation measures. However, doubts have been raised about the appropriate use of biodiversity offsets. We examined what no net loss means as a desirable conservation outcome and reviewed the conditions that determine whether, and under what circumstances, biodiversity offsets can help achieve such a goal. We propose a conceptual framework to substitute the often ad hoc approaches evident in many biodiversity offset initiatives. The relevance of biodiversity offsets to no net loss rests on 2 fundamental premises. First, offsets are rarely adequate for achieving no net loss of biodiversity alone. Second, some development effects may be too difficult or risky, or even impossible, to offset. To help to deliver no net loss through biodiversity offsets, biodiversity gains must be comparable to losses, be in addition to conservation gains that may have occurred in absence of the offset, and be lasting and protected from risk of failure. Adherence to these conditions requires consideration of the wider landscape context of development and offset activities, timing of offset delivery, measurement of biodiversity, accounting procedures and rule sets used to calculate biodiversity losses and gains and guide offset design, and approaches to managing risk. Adoption of this framework will strengthen the potential for offsets to provide an ecologically defensible mechanism that can help reconcile conservation and development. Balances de Biodiversidad y el Reto de No Obtener Pérdida Neta 相似文献
959.
《Environmental Hazards》2013,12(4):341-360
Downscaled climate models provide projections of how climate change may exacerbate the local impacts of natural hazards. The extent to which people facing exacerbated hazard conditions understand or respond to climate-related changes to local hazards has been largely overlooked. In this article, we examine the relationships among climate change beliefs, environmental beliefs, and hazard mitigation actions in the context of wildfire, a natural hazard projected to be intensified by climate change. We find that survey respondents are situated across a continuum between being ‘believers’ and ‘deniers’ that is multidimensional. Placement on this believer–denier spectrum is related to general environmental attitudes. We fail, however, to find a relationship between climate change beliefs and wildfire risk-reduction actions in general. In contrast, we find a statistically significant positive relationship between level of wildfire risk mitigation and being a climate denier. Further, certain pro-environmental attitudes are found to have a statistically significant negative association with the level of wildfire risk mitigation. 相似文献
960.
K. J. HENNENBERG C. DRAGISIC S. HAYE J. HEWSON B. SEMROC C. SAVY K. WIEGMANN H. FEHRENBACH U. R. FRITSCHE 《Conservation biology》2010,24(2):412-423
Abstract: The sustainable production of bioenergy is vital to avoiding negative impacts on environmental goods such as climate, soil, water, and especially biodiversity. We propose three key issues that should be addressed in any biodiversity risk‐mitigation strategy: conservation of areas of significant biodiversity value; mitigation of negative effects related to indirect land‐use change; and promotion of agricultural practices with few negative impacts on biodiversity. Focusing on biodiversity concerns, we compared principles and criteria set to address biodiversity and other environmental and social issues in seven standards (defined here as commodity‐based standards or roundtables, or relevant European legislation): five voluntary initiatives related to bioenergy feedstocks, the Renewable Transport Fuel Obligation (United Kingdom), and the European Renewable Energy Source Directive. Conservation of areas of significant biodiversity value was fairly well covered by these standards. Nevertheless, mitigation of negative impacts related to indirect land‐use change was underrepresented. Although the EU directive, with its bonus system for the use of degraded land and a subquota system for noncrop biofuels, offered the most robust standards to mitigate potential negative effects, all of the standards fell short in promoting agricultural practices with low negative impacts on biodiversity. We strongly recommend that each standard be benchmarked against related standards, as we have done here, and that efforts should be made to strengthen the elements that are weak or missing. This would be a significant step toward achieving a bioenergy industry that safeguards Earth's living heritage. 相似文献